content: /*
   * Copyright 2016-present David Karnok
   *
   * Licensed under the Apache License, Version 2.0 (the "License");
   * you may not use this file except in compliance with the License.
   * You may obtain a copy of the License at
   *
   *     http://www.apache.org/licenses/LICENSE-2.0
   *
   * Unless required by applicable law or agreed to in writing, software
   * distributed under the License is distributed on an "AS IS" BASIS,
   * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
   * See the License for the specific language governing permissions and
   * limitations under the License.
   */
  
  package hu.akarnokd.rxjava3.operators;
  
  import java.util.*;
  
  import org.reactivestreams.*;
  
  import io.reactivex.rxjava3.core.*;
  import io.reactivex.rxjava3.exceptions.Exceptions;
  import io.reactivex.rxjava3.functions.*;
  import io.reactivex.rxjava3.operators.ConditionalSubscriber;
  import io.reactivex.rxjava3.internal.subscriptions.*;
  import io.reactivex.rxjava3.plugins.RxJavaPlugins;
  
  /**
   * Buffer into the same buffer while the predicate returns true or
   * buffer into the same buffer until predicate returns true.
   *
   * @param <T> the source value type
   * @param <C> the buffer type
   *
   * @since 0.8.0
   */
  final class FlowableBufferPredicate<T, C extends Collection<? super T>> extends Flowable<C> implements FlowableTransformer<T, C> {
  
      enum Mode {
          /** The item triggering the new buffer will be part of the new buffer. */
          BEFORE,
          /** The item triggering the new buffer will be part of the old buffer. */
          AFTER,
          /** The item won't be part of any buffers. */
          SPLIT
      }
  
      final Publisher<T> source;
  
      final Predicate<? super T> predicate;
  
      final Mode mode;
  
      final Supplier<C> bufferSupplier;
  
      FlowableBufferPredicate(Publisher<T> source, Predicate<? super T> predicate, Mode mode,
              Supplier<C> bufferSupplier) {
          this.source = source;
          this.predicate = predicate;
          this.mode = mode;
          this.bufferSupplier = bufferSupplier;
      }
  
      @Override
      protected void subscribeActual(Subscriber<? super C> s) {
          C buffer;
  
          try {
              buffer = Objects.requireNonNull(bufferSupplier.get(), "The bufferSupplier returned a null buffer");
          } catch (Throwable ex) {
              Exceptions.throwIfFatal(ex);
              EmptySubscription.error(ex, s);
              return;
          }
  
          source.subscribe(new BufferPredicateSubscriber<>(s, buffer, predicate, mode, bufferSupplier));
      }
  
      @Override
      public Publisher<C> apply(Flowable<T> upstream) {
          return new FlowableBufferPredicate<>(upstream, predicate, mode, bufferSupplier);
      }
  
      static final class BufferPredicateSubscriber<T, C extends Collection<? super T>>
      implements ConditionalSubscriber<T>, Subscription {
  
          final Subscriber<? super C> downstream;
  
          final Predicate<? super T> predicate;
  
          final Mode mode;
  
          final Supplier<C> bufferSupplier;
  
          C buffer;
  
          Subscription upstream;
  
          int count;
  
          BufferPredicateSubscriber(Subscriber<? super C> downstream,
                  C buffer,
                  Predicate<? super T> predicate, Mode mode,
                  Supplier<C> bufferSupplier) {
              this.downstream = downstream;
              this.predicate = predicate;
              this.mode = mode;
              this.buffer = buffer;
              this.bufferSupplier = bufferSupplier;
          }
  
          @Override
          public void onSubscribe(Subscription s) {
              if (SubscriptionHelper.validate(this.upstream, s)) {
                  this.upstream = s;
  
                  downstream.onSubscribe(this);
              }
          }
  
          @Override
          public void onNext(T t) {
              if (!tryOnNext(t)) {
                  upstream.request(1);
              }
          }
  
          @Override
          public boolean tryOnNext(T t) {
              C buf = buffer;
              if (buf != null) {
                  boolean b;
  
                  try {
                      b = predicate.test(t);
                  } catch (Throwable ex) {
                      Exceptions.throwIfFatal(ex);
                      upstream.cancel();
                      buffer = null;
                      downstream.onError(ex);
                      return true;
                  }
  
                  switch (mode) {
                  case AFTER: {
                      buf.add(t);
                      if (b) {
                          downstream.onNext(buf);
  
                          try {
                              buffer = bufferSupplier.get();
                          } catch (Throwable ex) {
                              Exceptions.throwIfFatal(ex);
                              upstream.cancel();
                              onError(ex);
                              return true;
                          }
  
                          count = 0;
                      } else {
                          count++;
                          return false;
                      }
                      break;
                  }
                  case BEFORE: {
                      if (b) {
                          buf.add(t);
                          count++;
                          return false;
                      } else {
                          downstream.onNext(buf);
                          try {
                              buf = bufferSupplier.get();
                          } catch (Throwable ex) {
                              Exceptions.throwIfFatal(ex);
                              upstream.cancel();
                              onError(ex);
                              return true;
                          }
  
                          buf.add(t);
                          buffer = buf;
                          count = 1;
                      }
                      break;
                  }
                  default:
                      if (b) {
                          downstream.onNext(buf);
  
                          try {
                              buffer = bufferSupplier.get();
                          } catch (Throwable ex) {
                              Exceptions.throwIfFatal(ex);
                              upstream.cancel();
                              onError(ex);
                              return true;
                          }
  
                          count = 0;
                      } else {
                          buf.add(t);
                          count++;
                          return false;
                      }
                  }
              }
              return true;
          }
  
          @Override
          public void onError(Throwable t) {
              if (buffer != null) {
                  buffer = null;
                  downstream.onError(t);
              } else {
                  RxJavaPlugins.onError(t);
              }
          }
  
          @Override
          public void onComplete() {
              C b = buffer;
              if (b != null) {
                  buffer = null;
                  if (count != 0) {
                      downstream.onNext(b);
                  }
                  downstream.onComplete();
              }
          }
  
          @Override
          public void request(long n) {
              upstream.request(n);
          }
  
          @Override
          public void cancel() {
              upstream.cancel();
          }
      }
  }
  